Forum: F-16 Procedures

Hi All,
I am subrat.

Can F-16 fly and land safely if there is a complete hydraulic failure? & how?
Can F-16 fly and land safely if there is a complete electric failure? & how?
Can F-16 fly and land safely if there is a complete hydraulic failure & electric failure? & how?

Best Regards
Subrat.
subrat_sppl2007@[Link pending approval]

F-16.net Sponsor

The answers are no, no, and no.

Why not? That's what the EPU and Hydrazine is for. Assuming the aircraft is close enough to reach an airfield, the EPU will fire and provide both electrical and hydraulics...for a while. Viper drivers practice simulated flameout (SFO) landings quite frequently

Guess it depends on the definition of "complete". "Complete" to me means no hydraulic pressure from system A or system B and no electrical power from any generator or battery. It usually takes a number of things going wrong to end up in such a situation.

Rather than saying the EPU will fire and provide both electrical and hydraulics, I'd say the EPU should fire and ... The EPU doesn't always provide emergency power. Things like catalyst bed contamination and the H-70 tank serviced with water instead of H-70 have occurred.

If there's no hydraulic pressure or no electrical power, the pilot will be trusting the ACES II.

On the electrical side only, IIRC, there's also, in sequence, the PMG, the aircraft battery and the individual FLCS batteries (maybe something else I've missed).

Had a main generator CSD oil line come loose on the range, and an EPU that malfunctioned (fired initially, green light and then failed) and flew 100+ miles to an approach end arrestment. The HUD was a little flaky.

Hydraulics are not so 'layer upon layer' redundant, but personally never had a problem.
(F-4 was the hydraulic nightmare.)

"Complete" if taken literally, however, results in the "no, no, no"...literally. Shocked

EDIT: XFLTSAFETY beat me to it.

Thank you all for your answers.
Trying to figure it out all your answers to my previous queries.
Few more queries would like to ask related to F-16 & F-15

Q1)In F-16, If engine driven pump of system A & System B fails, then EPU Hydraulic Pump will take care of Rudder & flaperons, Flight control accumulator to horizontal tail.
a)What about landing gear and speed brakes??? whrz the hydraulic supply? i cannot figure it out from the circuit.
b) and what does LEF'S in the circuit mean?

[Link pending approval]) In f-15 Aircraft, If Power Control-1 system fails , Power control -2 fails, and utility system fails. that means all the hydraulic system fails, it tells that with Control Augmentation System (CAS), the pilot can land the aircraft safely. How does that happen without hydraulics? Can anybody suggest please?

Regards,
Subrat
subrat_sppl2007@[Link pending approval]

catchboy2006 wrote:

Q1)In F-16, If engine driven pump of system A & System B fails, then EPU Hydraulic Pump will take care of Rudder & flaperons, Flight control accumulator to horizontal tail.
a)What about landing gear and speed brakes??? whrz the hydraulic supply? i cannot figure it out from the circuit.
b) and what does LEF'S in the circuit mean?

The EPU hydraulic pump should pressurize hydraulic system A which provides hydraulic power for the rudder, flaperons, horizontal tails, speedbrakes, and one of the leading edge flap (LEF) motors. The system A flight control accumulator provides brief pressure support if pressure drops from high demand. The landing gear normally operates from hydraulic system B. Since that is no longer pressurized, landing gear extension requires use of the alternate pneumatic system.

Hi,
I believe nose wheel steering is run by hydraulic system B. Does that mean that it is not powered during an emergency landing with only EPU as a source of power? What about the wheel brakes? Would they be operational? Thanks
Shrimpman

Thank you sir for your reply.
Coming back to the Landing gear topic, Can we add an accumulator instead of a pneumatic system that can supply the required hydraulics to landing gear during the failure of system B? Like you said landing gear can only be operated by system B. Can we give a supply line from both system A & system B for increasing the redundancy of landing gear? Any draw backs if we do so?
Thank you,
Best Regards,
Subrat.

Dear Shrimpman,
We dont have to bother about parking the aircraft during emergency. The aim is to land the aircraft safely. Wheel brakes can be operated by brake & JFS accumulators & yes they can be operated. Guys please rectify me if am wrong.

Regards
Subrat.

NWS is not available if system B is not pressurized or if the landing gear alternate extension system is used. Subrat is correct about the wheel brakes.

Subrat - The existing pneumatic backup system works well. Replacing the pneumatic system with an accumulator system would not increase the redundancy of the landing gear IMHO. To do so would be costly for no benefit and would add more potential points for system A hydraulic failure. Plus, one would have to consider EPU hydraulic pump capability and system A accumulator capability to support flight control and speedbrake operation during landing gear extension.

P.S. I'm also curious who you are referring to when you say "can we add"?

Correct me if I'm wrong XFLTSAFE, but even with B system hydraulics available, if electrical power is supplied from layers below the EPU, i.e. Main gen & EPU malfunctions, NWS is not available.

I think that's why I ended up in the BAK-12. But it's been a long time (1987). Maybe the SOF just didn't trust my landing skill or lack of?

Very Happy

Mr. Larry Sir,
I am really sorry for not being addressing your name in my replies and [Link pending approval] you very much for your answers to my queries. Sir i am sorry i could not understand the abbreviation used Landing Gear IMHO. Also a bit of explanation about landing gear alternate extension ( What it has got to do with NWS)?

Thank you,
Subrat.

outlaw162 wrote:

Correct me if I'm wrong XFLTSAFE, but even with B system hydraulics available, if electrical power is supplied from layers below the EPU, i.e. Main gen & EPU malfunctions, NWS is not available.

I think that's why I ended up in the BAK-12. But it's been a long time (1987). Maybe the SOF just didn't trust my landing skill or lack of? Very Happy

You're right. NWS isn't on the battery bus; so, if you have lost electrical power from the main generator and the EPU generator (and standby generator for Blk 25 and on), you won't have NWS.

For your A/B model IFE, sounds like you were down to the aircraft battery for brakes, hook, etc. I imagine the SOF was more worried about how much time you'd still have aircraft battery power available; hence, the approach end cable engagement.

Dear all,
I have a [Link pending approval]
1. Do F-16 carry chip detector in its hydraulic circuit? Is it advisable to burn the contaminants in the hydraulic circuit??? my reply would be no for [Link pending approval]

Best Regards
Subrat

Forum: F-16 Procedures

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